Blunted or restricted affect is among the most persistent, characteristic features of schizophrenia. Assessment procedures devised to measure blunted affect remain fairly crude, and very little is known about the nature of the problem. The present proposal outlines two studies that will identify features of blunted affect that may be useful in distinguishing between schizophrenics with blunted affect and patients with other mental disorders, most notably depression. The proposed studies will also explore the breadth of blunting across a range of emotional categories and investigate the possibility that affective restriction may be influenced by situational or interpersonal variables. Facial expressions are the most specific, readily available nonverbal manifestations of an individual's emotional state. Facial action can be reliably divided into a large number of individual, anatomically-based action units. A variety of specific constellations of these units represent emotional prototypes. The proposed studies will employ Ekman and Friesen's Facial Action Coding System (FACS) to assess emotional reactions (or their absence) in various groups of psychiatric patients. In the first study, groups of blunted and nonblunted schizophrenics and moderately and severely depressed patients will be asked to provide short verbal descriptions of incidents from their past that made them feel happy, sad, surprised, afraid, angry, or disgusted. Their facial actions during these descriptions will be recorded on videotape and analyzed using FACS. In the second study, blunted and nonblunted schizophrenics and individuals with bipolar affective disorders (none of the patients in an active phase of their disorder) will be observed during interactions with two significant others: one who is considered high in "expressed emotion" and another who is not. The patients' facial actions will be analyzed following both critical and supportive comments made by each of the significant others. The long-term objectives of this line of research include the development of more sophisticated observational systems that can be used in clinical settings, the collection of prospective data comparing the predictive validity of blunted affect and other features of schizophrenia, and cross-cultural examinations of the role of blunted affect in schizophrenia.